质子交换膜燃料电池用6061铝合金极板表面类石墨碳涂层的导电耐蚀性能

Conductive and Corrosion-Resistant Properties of Graphite-like Carbon Coating on 6061 Aluminum Alloy Bipolar Plate for Proton Exchange Membrane Fuel Cell

为了获得6061铝合金极板表面类石墨碳涂层抗质子酸腐蚀的临界厚度和界面接触电阻的降低量值,采用磁控溅射方法在6061铝合金极板表面制备了一系列类石墨碳涂层。表征了类石墨碳涂层的微观结构,分析了涂层的界面接触电阻、耐蚀性和稳定性。结果表明,6061铝合金极板表面耐质子交换膜燃料电池阴极环境腐蚀的类石墨涂层临界厚度为0.97μm。与低碳靶电流条件下制备的涂层相比,碳靶电流4.5 A时制备的涂层表面更加光滑;此时,类石墨碳涂层的界面接触电阻最小,为16 mΩ·cm^(2),是石墨极板接触电阻的2倍。

In order to obtain the critical thickness of graphite-like carbon coating on 6061 aluminum alloy with the corrosion resistance against proton acid and the reduction value of interfacial contact resistance, a series of graphite-like carbon coatings were deposited on 6061 aluminum alloy plate by a magnetron sputtering system. The microstructure of the deposited coatings was characterized, and the interfacial contact resistance, corrosion resistance, and stability of the coatings were analyzed. Results show that the critical thickness of the graphite-like carbon coating on 6061 aluminum alloy with corrosion resistance against the proton acid in proton exchange membrane fuel cell cathode environment is 0.97 μm. Compared with the ones prepared at low carbon target currents, the coatings prepared at the carbon target current of 4.5 A show a smoother surface. When the carbon target current reaches4.5 A, the interfacial contact resistance is the lowest, reaching 16 mΩ·cm^(2), which is two times larger than that of the graphite bipolar plate.